11. SAVING SOIL MOISTURE. 



Illustrative material: Two lamp chimneys, a pan, fine soil 

 and coarse soil. 



Save Moisture in Soil. We learned in Lesson 2 that 

 water passes off the surface of the soil by evaporation, 

 and that other water comes from below to take its place. 

 We also learned in Lesson 3 that plants take large 

 amounts of water from the soil, and that few field crops 

 receive as much water as they need in summer. With 

 the proper knowledge, the farmer and the gardener may 

 do much to prevent the useless loss of moisture from the 

 soil in dry weather. 



Manure to Make Humus We learned in Lesson 8 

 that the presence of humus enables the soil to hold more 

 water. A soil that contains plenty of humus catches 

 more water when it rains than one that contains little 

 humus. It holds the water longer in dry weather. One 

 of the best ways to retain moisture in the soil is to use 

 plenty of barnyard and stable manure, and thus keep the 

 soil full of humus. Commercial fertilizers do not, to 

 any great extent, help the soil to retain water. 



Coarse and Fine Soil Compared. In the experiment 

 shown in Figure 23, the two lamp chimneys were filled 

 to the dotted line with dry soil that had been sifted 

 through a flour sieve. Enough of the soil that would 

 not pass through the sieve was then added to the left 

 chimney to raise the soil to the same height as that in 



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